He told the congregation he wanted to remember and share the country's shock and revulsion concerning the attacks on two children in the town.

"My prayer today is for the young victims, their families and local communities," he said.

A man has been charged in court in connection with the alleged attack.

Cardinal Sean Brady, the Papal Nuncio Archbishop Charles Brown and the outgoing Bishop Colm O' Reilly, who has retired, co-consecrated the service in Saint Mary's Pro-Cathedral.

Bishop Duffy said the Episcopal motto he has chosen is "I have come that they may have life" because each human life is so important.

"When I think of life I think of the great ability we can have to lift hearts and especially the hearts of those who are in dark places, maybe facing difficult choices or feeling abandoned, alone or of little worth or struggling financially, as many are," he said.

"I think of those whose passion for life and whose sensitivity to others conveys the message that life is worth living, the message of Jesus Christ."

Bishop Duffy, 53, was ordained a priest for the Diocese of Kilmore in June 1982, taught history, religion and Irish for 11 years in Saint Patrick's College, Cavan and was principal of Fatima and Felim's Secondary School, Ballinamore, Co Leitrim, for 12 years from 1996.

He was with the parish of Laragh, Co Cavan, before his appointment by Pope Francis and is now in control of Ardagh and Clonmacnois which includes 41 parishes covering Co Longford, most of Leitrim and parts of Cavan, Offaly, Roscommon, Sligo and Westmeath.

The senior churchman said he is eager to continue and build on the good work that the faithful and talented clergy of this diocese and their parish communities have accomplished.

"I am conscious that I need to listen, and to engage with, the people, priests and religious so that together and with God's help we can continue to build up the people of God in Ardagh and Clonmacnois," Bishop Duffy added.

"I look forward with great joy and enthusiasm to joining with you and to working and living among you in our mission of spreading the good news of Jesus Christ."